A senior British counter-terrorism police officer has gone on trial accused of offering to sell the News of the World newspaper inside information about a police investigation into alleged phone-hacking by some of its reporters.
The case of April Casburn is the first to come to criminal trial as a result of police investigations into wrongdoing at the Sunday tabloid, which was shut down by its owner Rupert Murdoch in July 2011.
The hacking scandal has caused upheavals at Murdoch's media empire and has embarrassed London's police and political establishment by revealing their close ties with journalists.
Casburn, 53, has pleaded not guilty to one charge of misconduct in public office. Her trial at London's Southwark Crown Court is expected to last three or four days.
The court heard Casburn had phoned the paper and disclosed that six people were being investigated including Andy Coulson, a former News of the World editor who was by then Prime Minister David Cameron's media chief.
"She sought to undermine a highly sensitive and high-profile investigation at the point of its launch," prosecutor Mark Bryant-Heron told the jury, opening the case.
"It was a gross breach of the trust that the public places in a police officer not to disclose information on a current investigation in an unauthorised way, or to offer to do so in the future for payment," he said.
Casburn made the call to the News of the World newsdesk early in the morning on September 11, 2010, a Saturday.
At the time, the hacking scandal was revving up following a New York Times article alleging that the problem had been widespread at the News of the World and not confined to one convicted "rogue reporter", as the newspaper had previously maintained.
The police had come under pressure for shelving a much earlier investigation into wrongdoing at the newspaper and had announced in the previous days that they were considering re-opening their investigations.
Casburn, who has the rank of detective chief inspector, was at that time head of a unit specialising in financial investigations related to counter-terrorism work.
She was not directly involved in the phone-hacking team that was being put together that week, but one of her specialist financial investigators had been drafted in.
According to former News of the World staffer Tim Wood, who took her phone call that Saturday morning, Casburn complained about the fact that "counter-terrorism assets" were being used for the hacking probe.
Wood said she also disclosed that six people were being investigated including Coulson, who is now facing criminal charges in connection with the phone-hacking scandal.
Casburn accepts that she made the call but disputes Wood's account of what she said. She says she did not ask for payment and did not disclose anything that had not been widely reported in the press in previous days.
There is no recording of the call, but Wood wrote an email summarising its content to the News of the World's news editor and senior crime correspondent about a quarter of an hour after hanging up.
In that email, the first exhibit in the case, Wood wrote that a person claiming to be a senior policewoman wanted to "sell inside info" about the investigation into phone-hacking.
Called to the witness box, Wood said he could no longer remember some details of the call but was confident that his email had been accurate, including on the issue of whether Casburn asked for money.
"I wouldn't have put that if she hadn't asked, or given an indication," he told the court.
The News of the World did not publish any article based on the information given by Casburn during the call, nor did it make any payment to her.
Casburn sat quietly in the glass dock at the back of the courtroom during Monday's hearing, wearing glasses, a dark jacket and skirt and black high-heel shoes. She will give evidence later in the trial.